| site-occupancy distribution modeling to correct population-trend estimates derived from opportunistic observations. | species' assessments must frequently be derived from opportunistic observations made by volunteers (i.e., citizen scientists). interpretation of the resulting data to estimate population trends is plagued with problems, including teasing apart genuine population trends from variations in observation effort. we devised a way to correct for annual variation in effort when estimating trends in occupancy (species distribution) from faunal or floral databases of opportunistic observations. first, for ... | 2010 | 20337672 |